Antimicrobial activity of amniotic fluid in South Indian women.

Samples of amniotic fluid obtained from 48 South Indian women in the third trimester of pregnancy were studied for antimicrobial activity. The growth of Staphylococcus albus, Candida albicans and Clostridium perfringens was inhibited by nearly all samples studied while the growth of Staphylococcus aureus, Escherichia coli and Bacteroides fragilis was inhibited by 50%, 42% and 18% of samples respectively. The growth of Streptococcus faecalis was not inhibited. Using radial immunodiffusion, IgG was measurable in all 10 samples studied (mean 23 mg/dl), whereas IgA was measurable in only three of these samples (mean 1.32 mg/dl). However, while specific IgA against C. albicans was detected by indirect immunofluorescence in 93% of samples, specific IgG against C. albicans was detected in only 26% of samples (P less than 0.001). Amniotic fluid obtained from parous women had greater inhibitory activity against E. coli (P less than 0.05) than did the amniotic fluid obtained from nulliparae.